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Charcot‐Marie‐Tooth (CMT) diseases are a heterogeneous group of genetic peripheral neuropathies caused by mutations in a variety of genes, which are involved in the development and maintenance of peripheral nerves. Myelin protein zero (MPZ) is expressed by Schwann cells, and MPZ mutations can lead to primarily demyelinating polyneuropathies including CMT type 1B. Different mutations demonstrate various forms of disease pathomechanisms, which may be beneficial in understanding the disease cellular pathology. Our molecular dynamics simulation study on the possible impacts of I30T mutation on the MPZ protein structure suggested a higher hydrophobicity and thus lower stability in the membranous structures. A study was also conducted to predict native/mutant MPZ interactions. To validate the results of the simulation study, the native and mutant forms of the MPZ protein were separately expressed in a cellular model, and the protein trafficking was chased down in a time course pattern. In vitro studies provided more evidence on the instability of the MPZ protein due to the mutation. In this study, qualitative and quantitative approaches were adopted to confirm the instability of mutant MPZ in cellular membranes.  相似文献   
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Background

Candida glabrata is a yeast that can cause hazardous fungal infections with high mortality and drug resistance.

Aims

The aim of this study was to determine the profile of drug susceptibility in clinical isolates of C. glabrata and review the resistance mechanisms to caspofungin.

Methods

A total of 50 C. glabrata clinical isolates from Iran were tested for in vitro susceptibilities to amphotericin B, caspofungin, fluconazole and voriconazole. To investigate the mechanism of resistance to caspofungin, hotspot areas of FKS1 and FKS2 genes were sequenced and gene expression profile was evaluated.

Results

All the isolates were susceptible to amphotericin B and caspofungin. Fluconazole resistance was exhibited in four isolates. In addition, only one isolate was resistant to voriconazole. FKS2 with 12 point mutations showed more mutations compared to FKS1 that had only two mutations. All substitutions were synonymous. FKS genes were expressed at comparable levels (no statistical significance) in caspofungin-treated and non-treated cultures.

Conclusions

The silent mutations in the hotspot areas of FKS genes and inconsiderable changes in gene expression were not associated with increased MIC (0.25 μg/ml). Other mechanisms of resistance which include mutations outside the hotspot area of FKS genes could be involved in a slight increase of MIC, and they should be identified through complete FKS gene sequencing.  相似文献   
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Two novel combination therapies for the treatment of benign prostatic hyperplasia were analyzed using simple and enhanced spectrofluorimetric methods based on derivative and derivative ratio techniques. The two combinations contained tamsulosin hydrochloride (TAM) as a minor component with tolterodine tartrate (TOL) or solifenacin succinate (SOL). The fluorescence of the three drugs under study was measured in methanolic water solution. For the TAM and SOL mixture, successful resolution between both drugs was achieved by derivative manipulation of both ratio and zero‐order emission spectra with good linearity in the ranges of 0.75–3.50 and 2.5–15.0 μg ml?1 for TAM and SOL, respectively. Extensive emission spectral overlap was observed for the TAM and TOL mixture. Therefore, only derivative application of the ratio emission spectra resolved such overlap and quantitated TAM and TOL simultaneously in the ranges 0.75–3.50 and 2.5–20.0 μg ml–1 for TAM and TOL, respectively. Optimization of various experimental parameters that affected the fluorescence intensity of the three drugs was performed. Successful application of all proposed methods was achieved for analysis of the two drugs in each combination therapy in their laboratory‐prepared mixtures and dosage forms with good accuracy and precision.  相似文献   
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DNA methylation occurs mostly at the C5 position of dinucleotide symmetric CpG sites in genomic DNA. A balance is maintained in the plant genome between DNA methylation mediated by RNA-directed DNA methylation (RdDM) and DNA demethylation mediated by the DEMETER (DME) protein family and REPRESSOR OF SILENCING (ROS1). We used double-stranded RNA (dsRNA) silencing to suppress ROS1 protein expression in ‘Nanlin895’ (Populus deltoides × Populus euramericana ‘Nanlin895’). Leaves of WT and transformant poplars revealed more symmetric methylation on CpG sites than roots and stems. In addition, leaves of transformant poplars revealed more methylated CpG sites in both 5.8S rDNA and histone H3 compared to WT types via 0, 50 and 100 mM NaCl treatments. In asymmetric methylation sites, transformant poplars exhibited more methylated CpHpG and CpHpH contexts than WT poplars. On the other hand, hypermethylation induced by PtROS1-RNAi construct resulted in pleiotropic phenotypic changes in transgenic poplars. The percentage of wavy leaves was increased maximum by ~45% in transgenic poplars. Also, the number of leaves was increased by ~200 number in transformants. Furthermore, shooting (%) and rooting (%) was decreased in transgenic poplars versus WT.  相似文献   
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Ischemia–reperfusion (IR) injury usually occurs during liver transplantation. Aquaporins (AQPs) are transmembrane channels that facilitate water permeability through cell membranes and are essential for the regulation of water homeostasis. Changes in the AQPs expression have been correlated with several inflammatory diseases. Less is known about AQPs expression in hepatic ischemia reperfusion injury. To clarify the roles of AQPs in IR injury, in this current study we examined the gene expression patterns of AQP1, 8 and 9 in the liver after IR injury. Male balb/c mice were exposed to partial (70%) hepatic ischemia for 65 min and then randomized into five groups of reperfusion [0 h (A), 8 h (B), 1 day (C), 3 days (D), and 7 days (E)]. A surgical group was also selected as the sham group. Serum and liver tissue samples were collected for evaluation of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and liver histopathology. Real time PCR was performed to evaluate the AQPs expression. I/R injury resulted in a significant increase in ALT and AST (p?<?0.05) compared to sham mice in each group. The gene expression of AQPs was significantly increased in the IR group compared with the sham group (p?<?0.05). AQP8 and AQP1 after 8 h (group B) showed the highest gene expression in comparison with other groups, but the highest level of AQP9 gene expression was observed after 1 day (group C). Pathologic changes in the liver after reperfusion were confirmed the IR. In the IR group cytoplasmic vacuolization, inflammatory cell infiltration and focal necrosis were detected. In conclusion, our findings indicated that the damage caused by ischemia–reperfusion in the liver can change the expression of AQP genes, which can interfere with hepatocellular homeostasis and their function. Upregulation of AQP1, 8 and 9 could contribute to the development of hepatocellular swelling after hepatic IR injury.  相似文献   
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